scholarly journals Distinct migratory pattern of naive and effector T cells through the blood–CSF barrier following Echovirus 30 infection

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Marie Wiatr ◽  
Carolin Stump-Guthier ◽  
Daniela Latorre ◽  
Stefanie Uhlig ◽  
Christel Weiss ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Choroid Plexus Papilloma ◽  
Effector T Cells ◽  
Cell Phenotype ◽  
Migration Process ◽  
Effector Cells ◽  
Echovirus 30 ◽  
Basolateral Side

Abstract Background Echovirus 30 (E-30) is one of the most frequently isolated pathogens in aseptic meningitis worldwide. To gain access to the central nervous system (CNS), E-30 and immune cells have to cross one of the two main barriers of the CNS, the epithelial blood–cerebrospinal fluid barrier (BCSFB) or the endothelial blood–brain barrier (BBB). In an in vitro model of the BCSFB, it has been shown that E-30 can infect human immortalized brain choroid plexus papilloma (HIBCPP) cells. Methods In this study we investigated the migration of different T cell subpopulations, naive and effector T cells, through HIBCPP cells during E-30 infection. Effects of E-30 infection and the migration process were evaluated via immunofluorescence and flow cytometry analysis, as well as transepithelial resistance and dextran flux measurement. Results Th1 effector cells and enterovirus-specific effector T cells migrated through HIBCPP cells more efficiently than naive CD4+ T cells following E-30 infection of HIBCPP cells. Among the different naive T cell populations, CD8+ T cells crossed the E-30-infected HIBCPP cell layer in a significantly higher number than CD4+ T cells. A large amount of effector T cells also remained attached to the basolateral side of the HIBCPP cells compared with naive T cells. Analysis of HIBCPP barrier function showed significant alteration after E-30 infection and trans- as well as paracellular migration of T cells independent of the respective subpopulation. Morphologic analysis of migrating T cells revealed that a polarized phenotype was induced by the chemokine CXCL12, but reversed to a round phenotype after E-30 infection. Further characterization of migrating Th1 effector cells revealed a downregulation of surface adhesion proteins such as LFA-1 PSGL-1, CD44, and CD49d. Conclusion Taken together these results suggest that naive CD8+ and Th1 effector cells are highly efficient to migrate through the BCSFB in an inflammatory environment. The T cell phenotype is modified during the migration process through HIBCPP cells.

scholarly journals Expression of T-cell differentiation antigens on effector cells in cell-mediated cytotoxicity in vitro. Evidence for functional heterogeneity related to the surface phenotype of T cells.

1975 ◽  
Vol 141 (1) ◽  
pp. 227-241 ◽  
Author(s):  
H Shiku ◽  
P Kisielow ◽  
M A Bean ◽  
T Takahashi ◽  
E A Boyse ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Killer Cell ◽  
Surface Antigens ◽  
Cell Phenotype ◽  
Direct Function ◽  
Effector Cells ◽  
Cell Functions ◽  
T Cell Antigens

The cell-mediated cytotoxicity (CMC) of nonadherent cells from the peritoneal cavity (NAPC) of alloimmunized mice can be measured by the [3H]proline microassay. The exhibition of thymus-derived (T) cell antigens on these killer cells was studied by incubating them with the relevant T-cell antisera and complement (C), under optimal conditions for lysis, before performance of the CMC assay. Under these conditions, the following T-cell antigens were demonstrable on the killer population in terms of percent reduction in CMC by the respective antisera: (a) Thy-1.1 (83%) and Thy-1.2 (100%), (b) MSLA (86%), (c) NTA-RA (a T-cell antigen recognized by naturally occurring autoantibody of NZB mice) (62%), (d) Ly1.1 )58%, (e) Ly-2.1 (11%; considered a marginal result) and Ly-2.2 (63%), and (f) Ly-3.2 (77%). The following were not demonstrable: (g) TL, and (h) Ly-1.2. (i) The antigen Ly-3.1 was not studied. Omission of C deprived all T-cell antisera tested of their capacity to suppress CMC, indicating that the cell components recognized by such antisera may perform no direct function in CMC. On the assumption that all Ly+ cells are Thy-1+, it is clear that the T-cell members of the immune NAPC population must be heterogenous. This follows from the fact that the proportions of T cells lysed by different Ly antisera did not correspond with ensuing degree of loss of CMC capacity. The extremes were represented by anti-Ly-1.2 (74% Thy-1+ cells lysed, but no reduction in CMC) and Ly-3.2 (54% Thy-1+ cells lysed, with 77% reduction in CMC). From this initial survey it appears that the C57BL/6 mice killer T-cell population active in CMC in vitro is relatively rich in surface antigens of the Ly-2/Ly-3 category and relatively poor in representation of the Ly-1 surface antigens. It remains to be seen whether this killer cell phenotype, poor in Ly-1 and rich in Ly-2/Ly-3, is characteristic of the mouse generally. From these results it appears that subsets of T cells with different immunological functions may exhibit qualitative or quantitative differences in surface antigens specified by different Ly loci; this will be easier to assess in the future when the results of experiments with the same Ly antisera but dealing with T-cell functions other than CMC become available.

scholarly journals γδ T Cells from Tolerized αβ T Cell Receptor (TCR)–deficient Mice Inhibit Contact Sensitivity-Effector T Cells In Vivo, and Their Interferon-γ Production In Vitro

1996 ◽  
Vol 184 (6) ◽  
pp. 2129-2140 ◽  
Author(s):  
Marian Szczepanik ◽  
Laurel R. Anderson ◽  
Hiroko Ushio ◽  
Wlodzimierz Ptak ◽  
Michael J. Owen ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Γδ T Cells ◽  
Interferon Γ ◽  
Effector T Cells ◽  
High Dose ◽  
Effector Cells

Contact sensitivity (CS) responses to reactive hapten Ag, such as picryl chloride (PCl) or oxazolone (OX), are classical examples of T cell–mediated immune responses in vivo that are clearly subject to multifaceted regulation. There is abundant evidence that downregulation of CS may be mediated by T cells exposed to high doses of Ag. This is termed high dose Ag tolerance. To clarify the T cell types that effect CS responses and mediate their downregulation, we have undertaken studies of CS in mice congenitally deficient in specific subsets of lymphocytes. The first such studies, using αβ T cell–deficient (TCRα−/−) mice, are presented here. The results clearly show that TCRα−/− mice cannot mount CS, implicating αβ T cells as the critical CS-effector cells. However, TCRα−/− mice can, after high dose tolerance, downregulate α+/+ CS-effector T cells adoptively transferred into them. By mixing ex vivo and then adoptive cell transfers in vivo, the active downregulatory cells in tolerized α−/− mice are shown to include γδ TCR+ cells that also can downregulate interferon-γ production by the targeted CS-effector cells in vitro. Downregulation by γδ cells showed specificity for hapten, but was not restricted by the MHC. Together, these findings establish that γδ T cells cannot fulfill CS-effector functions performed by αβ T cells, but may fulfill an Ag-specific downregulatory role that may be directly comparable to reports of Ag-specific downregulation of IgE antibody responses by γδ T cells. Comparisons are likewise considered with downregulation by γδ T cells occurring in immune responses to pathogens, tumors, and allografts, and in systemic autoimmunity.

scholarly journals Sunitinib Exerts In Vitro Immunomodulatory Activity on Sarcomas via Dendritic Cells and Synergizes With PD-1 Blockade

2021 ◽  
Vol 12 ◽  
Author(s):  
Darina Ocadlikova ◽  
Mariangela Lecciso ◽  
Javier Martin Broto ◽  
Katia Scotlandi ◽  
Michele Cavo ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
T Cells ◽  
Dendritic Cells ◽  
T Cell ◽  
Cell Lines ◽  
Effector T Cells ◽  
Sarcoma Cell ◽  
Ifn Γ ◽  
Sarcoma Cells

BackgroundHigh-grade sarcomas are a heterogeneous group of aggressive tumors arising in bone and soft tissues. After relapse, treatment options are limited. The multi-targeted receptor tyrosine kinase inhibitors (TKIs) sunitinib and inhibitor of PD-1 (anti-PD-1) nivolumab have shown antitumor activity in selected subtypes. In this study, we examine the role of TKIs and PD-1 based therapy in in vitro cocultures of sarcoma.MethodsThe human osteosarcoma (SaOS-2) and synovial sarcoma (SYO-1) cell lines were treated with sunitinib. After cell death and proliferation assessment, expression of PD-L1 was analyzed by flow cytometry. Sunitinib-treated sarcoma cells were cocultured with dendritic cells (DCs), and the phenotype of mature DCs was determined by flow cytometry. Mature DCs were cultured with autologous T cells. PD-1 expression on T cells, their proliferation, T regulatory cell (Tregs) induction and IFN-γ production, before and after nivolumab exposure, were analyzed.ResultsAlong with its anti-proliferative and direct pro-apoptotic effect on sarcoma cell lines, sunitinib prompted PD-L1 upregulation on sarcoma cells. Interestingly, sunitinib-treated sarcoma cells drive DCs to full maturation and increase their capacity to induce sarcoma-reactive T cells to produce IFN-γ. Conversely, no effect on T cell proliferation and T cell subpopulation composition was observed. Moreover, both bone and synovial sarcoma cell lines induced Tregs through DCs but sunitinib treatment completely abrogated Treg induction. Finally, sarcoma cell lines induced PD-1 upregulation on both effector T cells and Tregs when loaded into DCs, providing a rationale for using PD-1 blockade. Indeed, PD-1 blockade by nivolumab synergized with sunitinib in inducing IFN-γ-producing effector T cells.ConclusionsTaken together, our in vitro data indicate that the treatment of sarcoma cells with sunitinib can exert significant changes on immune cell subsets toward immune activation, leading to DC-based cross-priming of IFN-γ-producing effector T cells and reduced Treg induction. PD-1 blockade with nivolumab has a synergistic effect with sunitinib, supporting the use of TKI and anti-PD-1 approach in sarcomas, and perhaps in other cancers. DC-targeted drugs, including toll-like receptor 3 inhibitors and CD47 inhibitors, are under development and our preclinical model might help to better design their clinical application.

scholarly journals Dual T cell– and B cell–intrinsic deficiency in humans with biallelic RLTPR mutations

2016 ◽  
Vol 213 (11) ◽  
pp. 2413-2435 ◽  
Author(s):  
Yi Wang ◽  
Cindy S. Ma ◽  
Yun Ling ◽  
Aziz Bousfiha ◽  
Yildiz Camcioglu ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Cd4 T Cells ◽  
Ex Vivo ◽  
Cell Phenotype ◽  
Loss Of Function ◽  
Inborn Errors

Combined immunodeficiency (CID) refers to inborn errors of human T cells that also affect B cells because of the T cell deficit or an additional B cell–intrinsic deficit. In this study, we report six patients from three unrelated families with biallelic loss-of-function mutations in RLTPR, the mouse orthologue of which is essential for CD28 signaling. The patients have cutaneous and pulmonary allergy, as well as a variety of bacterial and fungal infectious diseases, including invasive tuberculosis and mucocutaneous candidiasis. Proportions of circulating regulatory T cells and memory CD4+ T cells are reduced. Their CD4+ T cells do not respond to CD28 stimulation. Their CD4+ T cells exhibit a "Th2" cell bias ex vivo and when cultured in vitro, contrasting with the paucity of "Th1," "Th17," and T follicular helper cells. The patients also display few memory B cells and poor antibody responses. This B cell phenotype does not result solely from the T cell deficiency, as the patients’ B cells fail to activate NF-κB upon B cell receptor (BCR) stimulation. Human RLTPR deficiency is a CID affecting at least the CD28-responsive pathway in T cells and the BCR-responsive pathway in B cells.

scholarly journals Short-Lived Effector CD8 T Cells Induced by Genetically Attenuated Malaria Parasite Vaccination Express CD11c

2013 ◽  
Vol 81 (11) ◽  
pp. 4171-4181 ◽  
Author(s):  
Laura A. Cooney ◽  
Megha Gupta ◽  
Sunil Thomas ◽  
Sebastian Mikolajczak ◽  
Kimberly Y. Choi ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Inflammatory Cytokines ◽  
Plasmodium Yoelii ◽  
T Cell Response ◽  
Parasite Development ◽  
Effector Memory ◽  
Cell Phenotype ◽  
Effector Cells ◽  
Ifn Γ

ABSTRACTVaccination with a single dose of genetically attenuated malaria parasites can induce sterile protection against sporozoite challenge in the rodentPlasmodium yoeliimodel. Protection is dependent on CD8+T cells, involves perforin and gamma interferon (IFN-γ), and is correlated with the expansion of effector memory CD8+T cells in the liver. Here, we have further characterized vaccine-induced changes in the CD8+T cell phenotype and demonstrated significant upregulation of CD11c on CD3+CD8b+T cells in the liver, spleen, and peripheral blood. CD11c+CD8+T cells are predominantly CD11ahiCD44hiCD62L−, indicative of antigen-experienced effector cells. Followingin vitrorestimulation with malaria-infected hepatocytes, CD11c+CD8+T cells expressed inflammatory cytokines and cytotoxicity markers, including IFN-γ, tumor necrosis factor alpha (TNF-α), interleukin-2 (IL-2), perforin, and CD107a. CD11c−CD8+T cells, on the other hand, expressed negligible amounts of all inflammatory cytokines and cytotoxicity markers tested, indicating that CD11c marks multifunctional effector CD8+T cells. Coculture of CD11c+, but not CD11c−, CD8+T cells with sporozoite-infected primary hepatocytes significantly inhibited liver-stage parasite development. Tetramer staining for the immunodominant circumsporozoite protein (CSP)-specific CD8+T cell epitope demonstrated that approximately two-thirds of CSP-specific cells expressed CD11c at the peak of the CD11c+CD8+T cell response, but CD11c expression was lost as the CD8+T cells entered the memory phase. Further analyses showed that CD11c+CD8+T cells are primarily KLRG1+CD127−terminal effectors, whereas all KLRG1−CD127+memory precursor effector cells are CD11c−CD8+T cells. Together, these results suggest that CD11c marks a subset of highly inflammatory, short-lived, antigen-specific effector cells, which may play an important role in eliminating infected hepatocytes.

scholarly journals Immunoregulation induced by autologous serum collected after acute exercise in obese men: a randomized cross-over trial

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Gilson P. Dorneles ◽  
Igor M. da Silva ◽  
Maeli Andressa Santos ◽  
Viviane R. Elsner ◽  
Simone G. Fonseca ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Exhaustive Exercise ◽  
Autologous Serum ◽  
Exercise Session ◽  
Cell Phenotype ◽  
Histone H4 ◽  
Post Exercise ◽  
Tnf Α

AbstractIn this study, we evaluated the effects of autologous serum collected after two types of exercise on the in vitro inflammatory profile and T cell phenotype of resting peripheral blood mononuclear cells (PBMCs) in obese men. Serum samples and PBMCs were obtained from eight obese men who performed two exercise bouts—high intensity interval exercise (HIIE) and exhaustive exercise session to voluntary fatigue—in a randomized cross-over trial. Pre-exercise PBMCs were incubated with 50% autologous serum (collected before and after each exercise bout) for 4 h. In vitro experiments revealed that post-HIIE serum reduced the histone H4 acetylation status and NF-κB content of PBMCs and suppressed the production of both TNF-α and IL-6 by PBMCs, while increasing IL-10 production. Post-exhaustive exercise serum induced histone H4 hyperacetylation and mitochondrial depolarization in lymphocytes and increased TNF-α production. In vitro post-HIIE serum incubation resulted in an increase in the frequencies of CD4 + CTLA-4 + and CD4 + CD25+ T cells expressing CD39 and CD73. Post-exhaustive exercise serum decreased the frequency of CD4 + CD25 + CD73+ T cells but increased CD4 + CD25-CD39 + T cell frequency. Both post-exercise serums increased the proportions of CD4 + PD-1 + and CD8 + PD-1+ T cells. Blood serum factors released during exercise altered the immune response and T cell phenotype. The type of exercise impacted the immunomodulatory activity of the post-exercise serum on PBMCs.

scholarly journals Phenotype, distribution, generation, and functional and clinical relevance of Th17 cells in the human tumor environments

Blood ◽  
2009 ◽  
Vol 114 (6) ◽  
pp. 1141-1149 ◽  
Author(s):  
Ilona Kryczek ◽  
Mousumi Banerjee ◽  
Pui Cheng ◽  
Linhua Vatan ◽  
Wojciech Szeliga ◽  
...  
Keyword(s):  
T Cells ◽  
Tumor Microenvironment ◽  
Regulatory T Cells ◽  
Cancer Patients ◽  
Th17 Cells ◽  
Human Tumor ◽  
Active Role ◽  
Effector T Cells ◽  
Cell Phenotype ◽  
Effector Cells

Abstract Th17 cells play an active role in autoimmune diseases. However, the nature of Th17 cells is poorly understood in cancer patients. We studied Th17 cells, the associated mechanisms, and clinical significance in 201 ovarian cancer patients. Tumor-infiltrating Th17 cells exhibit a polyfunctional effector T-cell phenotype, are positively associated with effector cells, and are negatively associated with tumor-infiltrating regulatory T cells. Tumor-associated macrophages promote Th17 cells through interleukin-1β (IL-1β), whereas tumor-infiltrating regulatory T cells inhibit Th17 cells through an adenosinergic pathway. Furthermore, through synergistic action between IL-17 and interferon-γ, Th17 cells stimulate CXCL9 and CXCL10 production to recruit effector T cells to the tumor microenvironment. The levels of CXCL9 and CXCL10 are associated with tumor-infiltrating effector T cells. The levels of tumor-infiltrating Th17 cells and the levels of ascites IL-17 are reduced in more advanced diseases and positively predict patient outcome. Altogether, Th17 cells may contribute to protective human tumor immunity through inducing Th1-type chemokines and recruiting effector cells to the tumor microenvironment. Inhibition of Th17 cells represents a novel immune evasion mechanism. This study thus provides scientific and clinical rationale for developing novel immune-boosting strategies based on promoting the Th17 cell population in cancer patients.

Suppression of CTL Responses against AAV-Capsid Epitopes by Peptide-Induced Regulatory T Cells.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 377-377 ◽  
Author(s):  
Daniel J Hui ◽  
Gary C Pien ◽  
Etiena Basner-Tschakarjan ◽  
Federico Mingozzi ◽  
Jonathan D Finn ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Regulatory T Cells ◽  
Cd8 T Cells ◽  
Transgene Expression ◽  
T Cell Responses ◽  
Effector Cells ◽  
Cell Responses ◽  
Ctl Activity

Abstract Abstract 377 Hemophilia B represents a promising model for the development of adeno-associated viral (AAV) vectors-based gene therapeutics. In the first clinical trial for AAV serotype 2 mediated gene transfer of Factor IX (F.IX) to the liver of severe hemophilia B subjects, transgene expression was short-lived with a gradual decline of F.IX levels. The loss of transgene expression was accompanied by a transient transaminitis, which we hypothesized to be the result of the reactivation of a pool of capsid-specific memory CD8+ T cells originated from a previous exposure to wild-type AAV. These results were unanticipated since previous work in small and large animal models showed that AAV administration is uneventful, allowing prolonged expression of F.IX transgene at therapeutic levels. We developed an in vitro cytotoxicity assay using a human hepatocyte cell line expressing HLA-B*0702, a common MHC class I allele for which the AAV capsid immunodominant epitope VPQYGYLTL was identified. Using this model, we demonstrated that HLA-matched AAV-specific effector CD8+ T cells were able to lyse target hepatocytes transduced with AAV-2. We now use this in vitro model of CTL killing of AAV-transduced hepatocytes to demonstrate the efficacy of a novel strategy to circumvent undesirable immune response through the engagement of regulatory T cells. A recently characterized MHC Class II-restricted T cell epitope (Tregitope) in the Fc fragment of IgG has been shown to induce regulatory T cells in vitro and in vivo (Blood, 2008; 112: 3303-3311). AAV-specific HLA-B*0702 effector cells expanded in the presence of a human Tregitope peptide resulted in 79% to 89% inhibition of cytotoxic activity against peptide-pulsed and AAV-transduced target cells, respectively. These results were confirmed using PBMCs from 5 different donors. A similar degree of inhibition of CTL activity was observed for the HLA allele A*0101, which binds to the AAV-derived epitope SADNNNSEY; co-culture of effector cells with the Tregitope inhibited CTL-mediated killing by 60%. Interestingly, the same Tregitope efficiently mediated suppression of CTL activity in subjects carrying different HLA alleles, indicating a high level of promiscuity of Tregitope binding. Staining for the regulatory T cell markers CD4, CD25, and FoxP3 supported the hypothesis that Tregitopes suppress T cell responses by expanding regulatory T cells; 62.2% of the CD4+ population stained positive for CD25 and FoxP3 in PBMCs expanded against AAV epitopes in the presence of Tregitope, compared with PBMCs expanded against an AAV epitope alone (3.63%), or against an AAV epitope and an irrelevant control peptide (1.94%). Polyfunctional analysis for markers for T cell activation showed that CD8+ T cells incubated in the presence of Tregitope had an approximately 5-fold decrease in production of IL-2 and IFN-γand a 2-fold reduction in TNF-α production, indicating levels of activation close to naïve CD8+ T cells. We further characterized the mechanism of action of Tregitopes by showing that Tregitopes are required at the time of CD8+ T cell priming, as CTL activity of AAV-expanded CD8+ T cells against transduced hepatocytes was not inhibited by the CD4+ T cell fraction of PBMC expanded separately in vitro with Tregitopes only. We conclude that the use of Tregitopes represents a promising strategy for antigen-specific, Treg-mediated modulation of capsid-specific T cell responses. Disclosures: Martin: EpiVax: Employment. De Groot:EpiVax, Inc.: Employment, Equity Ownership.

Effective Prevention of Acute Graft-Verses-Host Disease by Targeting PKC Alpha and PKC Theta in Mice

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1898-1898
Author(s):  
Kelley M.K. Haarberg ◽  
Crystina Bronk ◽  
Dapeng Wang ◽  
Amer Beg ◽  
Xue-Zhong Yu
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Acute Gvhd ◽  
T Cell Signaling ◽  
Effector Cells ◽  
T Effector Cells ◽  
Immunologic Synapse

Abstract Abstract 1898 Protein kinase C theta (PKCθ), a T cell signaling molecule, has been implicated as a therapeutic target for several autoimmune diseases as well as graft-versus-host disease (GVHD). PKCθ plays a vital role in stabilization of the immunologic synapse between T effector cells and antigen presenting cells (APC), but has been shown to be excluded from the immunologic synapse in T regulatory cells (T reg). PKCθ inhibition reduces the alloreactivity of donor T cells responsible for induction of GVHD while preserving graft-versus-leukemia (GVL) responses. The roles of PKCθ and the potential compensatory alpha isoform (PKCα) are not clearly defined with regard to alloresponses or T cell mediated responses in GVHD. In this context, we measured PKCθ and PKCα/θ gene deficient T cell activation upon TCR-ligation in vitro using [3H]-TdR incorporation and CSFE labeling assays. T cells from PKCθ and PKCα/θ gene deficient donor mice were utilized in vivo in a pre-clinical allogenic murine model of myeloablative bone marrow transplantation (BMT). The development of GVHD was monitored in recipient mice with or without injection of A20-luciferase cells to observe the progression of GVL in vivo. Combined blockade of PKCα and PKCθ causes a significant decrease in T cell proliferation compared to blocking PKCθ alone in vitro. Deficiency in PKCα and PKCθ had no effect on immune reconstitution following irradiation and BMT in vivo. Even with a high transplant load of 5×106 CD4+ and CD8+ T cells, PKCα/θ deficient (PKCα/θ−/−) T cells failed to induce acute GVHD. Our data suggest that the ability of double deficient T cells to induce GVHD was further reduced than PKCθ-deficient T cells. Additionally, a greater number and percentage of B220+ B cells and FoxP3+ T regs were isolated from the spleens of PKCα/θ−/− T cell recipient mice 120 after BMT than were isolated from wild type (WT) or PKCθ−/− T cell recipients. Fewer CD4+ or CD8+ T effector cells were isolated from the spleens of PKCα/θ−/− T cell recipient mice 120 after BMT than were isolated from wild type or PKCθ−/− T cell recipients. Importantly, the activity of B cells isolated from PKCα/θ−/− T cell recipient mice 120 after BMT was greater on a per cell basis, while the activity of T effector cells isolated from these mice was greatly reduced compared to WT or PKCθ−/− T cell recipients. While not absent, GVL was reduced in PKCα/θ−/− T cell recipient mice when compared to WT or PKCθ−/− T cell recipients. This work demonstrates the requirement of PKCα and θ for optimal activation and function of T cells in vitro. These experiments highlight a potential compensatory role for PKCα in the absence of PKCθ in T cell signaling and activation. Combined deficiency of PKCα and θ prevents induction of acute GVHD while improving the maintenance of splenic cellularity in PKCα/θ T cell recipient mice. Additionally, PKCα/θ dual deficient T cell transplant shifts the splenic balance toward a greater number and percentage of T reg and B cells and away from T effector cells following BMT. The reduced and sub-optimally active T effector cells isolated from PKCα/θ−/− T cell recipient mice in combination with reduced GVL stresses the importance of PKCα and θ molecules and their roles in T cell activity in the context of both GVHD and GVL. Dual deficiency of PKCα/θ is associated with a decline of T effector function that is optimal for the amelioration of GVHD, but is perhaps too reduced to substantially maintain effective GVL. Modulation of PKCα and θ signaling presents a valid avenue of investigation as a therapeutic option for GVHD. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Elimination of syngeneic sarcomas in rats by a subset of T lymphocytes.

1980 ◽  
Vol 152 (4) ◽  
pp. 823-841 ◽  
Author(s):  
E Fernandez-Cruz ◽  
B A Woda ◽  
J D Feldman
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Cell Subset ◽  
Suppressor Cells ◽  
Effector Cells ◽  
Long Duration ◽  
Ia Antigens

Established subcutaneous Moloney sarcomas (MST-1) of large size and long duration were eliminated from syngeneic rats by intravenous infusion of varying numbers of specific syngeneic effector T lymphocytes. Spleen cells from BN rats in which tumor had regressed were cultured in an in vitro mixed lymphocyte tumor cell culture (MLTC) to augment cytotoxicity of effector cells. In the MLTC a T cell subset was expanded in response to MST-1 antigens and transformed into blast elements. With these changes, there was an increase in the W3/25 antigen on the T cell surface, a decrease of W3/13 antigen, and an increase in the number of T cells with Ia antigens. The subset associated with elimination of established tumors was a blast T cell W3/25+, W3/13+, as detected by monoclonal antibodies to rat T antigens. The W3/25+ subset was poorly cytotoxic in vitro for MST-1 and apparently functioned in vivo as an amplifier or helper cell in the tumor-bearing host. The W3/25- population was a melange of cells that included (W3/13+, W3/25-) T cells, null cells, Ig+ cells, and macrophages, and was associated with enhancement of tumor in vivo, suggesting the presence of suppressor cells.

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